Material spreaders are commonly used to spread salt, sand, or salt and sand mixtures over a surface to control ice and snow on the surface. There are many types of spreader assemblies, examples of such assemblies are shown in U.S. Pat. Nos. 6,089,478; D425,915; 6,422,490; and 7,347,390 all assigned to the assignee of the present application.
Known spreaders have a hopper for containing the material to be spread and use for example an auger or conveyor to move the material to the discharge opening of the hopper. In some units, the material is discharged directly from the discharge opening to the surface to be treated. In others, there is a spinner adjacent the discharge opening that receives the material and distributes the material by spinning and throwing the material over the surface to be treated.
One problem with these known spreaders is that they are not well suited to treat smaller surfaces. For example, sidewalks require a smaller amount of material to be spread over a much smaller area. Known spreaders over-spread material on sidewalks, since they are not readily capable of spreading smaller amounts over smaller areas. Known spreaders will distribute too much material and will spread the material beyond the desired area. This results in excessive material being spread, wasting resources, and material being spread over undesired areas, such as vegetation, which can be detrimental to the vegetation.
Additionally, known spreaders also have a gate that is adjusted manually which requires a speed change or gate change to have different output.
The present invention as described below, overcomes these problems with known material spreaders.